In U.S. Pat. Appln. Ser. No. 732,829, filed Oct. 15, 1976 now U.S. Pat. No. 4,156,008 and in U.S. Pat. Nos. 3,575,999 and 4,079,062 there are described a number of 1-(2-aryl-1,3-dioxan-2-ylmethyl)-1H-imidazoles and 1H-1,2,4-triazoles and a number of 1-(2-aryl-1,3-dioxolan-2-ylmethyl)-1H-imidazoles and 1H-1,2,4-triazoles, wherein the 1,3-dioxolane-moiety is substituted with one alkyl group or two methyl groups. The compounds of the present invention differ from the foregoing essentially by the presence on the 4 and 5 positions of the dioxolane ring of either two alkyl groups, one of which has at least 2 carbon atoms, or, a tetramethylene bridge.